now we are in the touchscreen phase. a consumer friendly touchscreen 3 years ago was unrealistic.
I have created touch friendly phone/pda setups over the past eight years for enterprises. So it was quite possible to do with the hard/software.
It simply wasn't being done for consumers. But it could've been, if everyone else hadn't been so tied to legacy systems and apps.
Touchscreens aren't going to take over. They'll just remain one of several types of setups, as they always have. Flip phones, sliders, keypads, etc aren't going away.